In the prior art there are various principles for how contacts of an electrical plug connector are fastened in the contact body or contact support of the plug connector.
A common variant is the engagement of the contacts in a latching manner by means of one or more spring arms that are fastened directly to the contacts and are supported in equivalent corresponding clearances in the contact support or allow themselves to become latched there.
Such contacts are typically fitted once into the contact support and become permanently latched there, i.e. if it were attempted to release the contact from the contact support, the resilient latching arms would be bent or damaged.
Further solutions for releasably latching contacts in the contact support can be found in the prior art, solutions in which special tools are used to allow the contacts to be operated from the outside and arranged re-releasably in the contact support.
However, there is the problem with the plug connectors known from the prior art that, with increasing miniaturization of the plug connectors and the requirement for higher current carrying capacity, proven contact latching principles lead to large structural forms.
In particular, the air gaps and creepage distances for plug connectors must conform to IEC 61984 or IEC 60664-1 and be dimensioned appropriately in accordance with the application area. Under this premise, there are problems on the one hand in maintaining sufficient distance between the contacts but also on the other hand of making plug connectors sufficiently small.
It is therefore intended to prevent metallic contact latching arms or other latching principles of one contact with respect to the other contact from leading to great relative distances between the contacts.
In other words, an object of the present invention is to provide a simpler, more reliable and more favorable locking and latching of contacts in a contact support while maintaining the required air gaps and creepage distances.
The basic concept of the invention is to latch the contacts in the plug connector by means of a locking element, preferably a coded locking element, to be precise in such a way that the coding element can be inserted into the contact support from the outside, into a locking position intended for it, whereby the contact is fixed and latched in its intended mounting position by a locking portion of the locking element.
In an advantageous way, the following forms of design have been preferred here:                the contacts are preferably provided with a peripheral annular groove, into which the locking means can engage in order to fix the contacts on the contact support;        the contact support has openings, into which locking elements can be inserted into the contact chamber of the contact support in order to come into connection there, preferably in a positively engaging manner and possibly in a nonpositively engaging manner, with the contact at the previously mentioned peripheral groove;        also preferably, the openings in the contact support between the contact chambers and the outer shell of the contact support are formed in such a way that the locking elements are held in the openings in a clamping manner;        with preference, the locking elements have coding lugs or coding ribs, which can engage into corresponding coding grooves on the contact support, in order to ensure that the respectively correct locking element is inserted into the intended opening in the contact support, in order to fix the contact mounted there;        each locking element can only be pushed completely into the contact support and lock there if the contact is arranged at its intended position in the contact chamber, and so the locking elements also assume the function of ensuring that a correct contact position in the contact support is ensured;        in a further advantageous configuration, the locking elements allow themselves to be pushed completely into the contact support, and so they finish flush with the surface of the contact support, whereby it is ensured that the plug connector can only be inserted into a corresponding mating connector if the contacts and locking elements have been introduced correctly and completely. This provides a function that ensures that the contacts are held reliably by the locking elements and the locking elements have been inserted in their intended latching position.        